Multi-stage intercooled compressor



9 H. HORNSCHUCH 3,355,096

MULTI-STAGE INTERCOOLED COMPRESSOR Filed Feb. 15, 1966 6 Sheets-Sheet l INVENTOR, HANNS HORNSCHUCH 6 Sheets-Sheet 2 Filed Feb. 15, 1966 INVENTOR. HA NNS HORNSGHUCH Nov. 28, 1967 H. HORNSCHUCH MULTI-STAGE INTERCOOLED COMPRESSOR Filed Feb. 15, 1966 6 Sheets$heet 5 INVENTOR- HANNS HORMSCHUCH Nov. 28, 1967 H. HORNSCHUCH 3,355,096

MULTI-STAGE INTERCOOLED COMPRESSOR I Filed Feb. 15, 1966 6 Sheets-Sheet- 4 INVENTOR HAN/VS HORNSCHUGH FIG. 4

Nov..28, 1967 Filed Feb. 15, 1966 H. HORNSCHUCH MULTI-STAGE INTERCOOLED COMPRESSOR 6 Sheets-Sheet 5 INVENTOR.

HA NNS HORNSCHUCH Nov. 28, 1967 H. HORNSCHUCH 3,355,096

MULTI'STAGE INTERCOOLED COMPRESSOR Filed Feb. 15, 1966 6 Sheets-Sheet 6 lNVENTOR HA NNS HORNSCHUCH United States Patent 6 5,09 MULTI-STAGE' INTERCOOLED COMPRESSOR Hanns- Hornschuch, Easton, Pa., assignor to Ingersoll- Rand Company, New York, N.Y-., a corporation of NewJersey Filed Feb. 15, 1966, Ser. No. 527,707 18 Claims. (Cl. 230-42 09) This invention relates to compressors and has more particular reference to the provision of a new and improved multi-stage rotary compressor having means for cooling the fluid compressed by its stage compressors.

conventionally, the provision of intercooling. means in a multi-stage rotary compressor, such as a multi-stage centrifugal compressor, has necessitated exposed external, piping between the individual stage compressors and the intercooling means. This external piping has, by necessity, required compensation for variation in length arising as a result of temperature changes caused by the temperature diflerentials inherent in conventional multi-stage, intercooled, rotary compressors. This external piping,"further more, has necessitated that conventional multi-stage, intercooled, rotary comp essors be constructed with an undesirably large centerline height which made compressor accessibility extremely diflicult.

An object of the present invention is to provide a new. and improved multi-stage, intercooled, rotary compressor wherein the individual stage compressors are connected to the intercooling means without the necessity for exposed external piping therebetween, and the intercooling means. and the stage compressors are relatively arranged to facilitate the compactness and accessibility of the compressor.

Another object of the invention is to provide a new and improved mulli-stage, intercooled, rotary compressor of the type set forth wherein the intercooling means are constructed and arranged to provide high efliciency cooling of the stage compressors and the fluid compressed thereby.

The foregoing objects and the other objects and advantages of the invention which will be apparent from the following description taken in connection with the accompanying drawings, are accomplished by the provision of a multi-stage, intercooled, rotary compressor comprising a housing having a body portion and a cover portion detachably connected to the body portion. An inlet means is provided in the housing for admitting fluid to be compressed into the housing; an outlet means is provided in the housing for. discharging compressed fluid. from. the. housing. A plurality. of stage rotary compressors, each having an inlet conduit and an outlet conduit, are disposed within the body portion of the housing and driven by a driving. means whIch isv operativelyv connected there-; to. A. plurality of cooler-means are disposed in the cover portion of the housing and connected to coolant conduit means which convey. coolant fluid to. the cooler means and discharge coolant fluid therefrom, the coolant conduit means preferably including a first section disposed within 3,355,096 Pat nted Nov- 28, 19 7 the body portion of the housing and a second, communicating, section carried by the cover portion of the housing. An inlet conduit means communicates the inlet means with the inlet conduit of a first of the stage compressors for conveying fluid from the inlet means to the inlet conduit oi the first of the stage compressors. An outlet con.- duit means communicates the outlet means with the outlet conduit of a, second of the stage compressors for convey.- ing fluid discharged through the outlet conduit of the sec: 0nd of the stage compressors to the outlet means. A plural ty of intermediate conduit means are carried by the cover portion of the housing and each extend adjacent one of the cooler means such that fluid passing through the intermediate conduit means is cooled by one of the cooler means. The intermediate conduit means are each disposed such that their opposing ends communcate with the inlet conduit of one of the stage compressors and the outlet conduit of another thereof such that fluid discharged through the outlet conduit of the first of the stage compressors passes serially through the others of the stage compressors before entering the inlet conduit of the second thereof.

Referring to the drawings wherein several embodiments of the invention have been given for the purposes of illustration only:

FIG. 1 is an external view in perspective of a multistage, intercooled, centrifugal compressor constructed in accordance with one embodiment of the present invention;

FIG. 2 is a view in perspective of the centrifugal COIl'l'. pressor shown in FIG. 1, illustrating such with the cover portion of the compressor moved to facilitate access to the compressor;

FIG. 3 is an enlarged s de view, partially broken away and in section, of the centrifugal. compressor illustrated in FIGS. 1 and 2;

FIG. 4 is a sectional view of the centrifugal compressor illustrated in FIGS. 1 through 3 taken on line 4-4 of FIG. 3, looking in the direction of the arrows, wherein the flow of the fluid being compressed is shown by arrows;

FIG. 5 is an enlarged fragmentary view of the centrifugal compressor illustrated in FIGS. 1 through 4, showing the first stage compressor thereof in relation to its intercooler; and

FIG. 6 is a view in perspective of a multi-stage centrifugal compressor constructed in accordance with an alternative embodiment of the present invention showing such with the cover portion of the compressor moved to facilitate access to the compressor.

Referring more particularly to the draw ngs wherein similar reference characters designate corresponding parts throughout the several views, FIGS. 1 through 5 illustrate a multi-stage intercooled, centrifugal compressor which is constructed in accordance w th one embodiment of the present invention. The centrifugal compressor comprises a housing designated generally at 10 which is supported by a plurality of leg members 12 projecting vertically from a horizontally extending, supporting base 14. The centrifugal compressor is driven by a driving motor 16 which is carried by a motor platform 18, supported by a plurality of leg members 20, projecting vertically from the supporting base 14. The hous ng 10, the driving motor 16, and the supporting base 14 form a unitary structure for facilitating the transportation and location of the centrifugal compressor.

The'housing 10: is formed to include a concave or dished body portion 22 having an open horizontal end, and a concave or dished cover portion 24 carried by the body portion- 22 and closing the open horizontal end thereof. The cover portion 24 is d'etachably connected to the body portion 22 by a plurality of bolts 26 whichv are disposed through. aligned openings in mating, annular flanges 23 and: 25: formed circumferentiallyaround the body portion 22 and the cover portion 24, respectively. The cover portion 24 is also detachably connected to the body portion 22 by an axially located retaining bolt 28 which extends through the cover portion 24 and is threaded into a bore 30 formed in a cyilndrical locking member 32 axially carried by the body portion 22. The bolts 26 and the retaining bolt 28 retain the annular flange 25 on the cover portion 24 in abutment with the annular flange 23 on the body portion 22 to prevent fluid leakage between the cover portion 24 and the body portion 22. An annular gasket (not shown) may be disposed between the annular flanges 23 and 25 to ensure the maintenance of a leak proof seal between the body and cover portions of the housing 10.

As illustrated in FIG. 2, the cover portion 24 may be hinged to the body portion 22 by a hinge pin 34 disposed through aligned openings formed in mating hinge arms 36 and 38 carried by the cover portion 24 and the body portion 22, respectively. This construction has been found to be particularly desirable in that it permits access to the interior of the housing without the necessity that a crane or the like be provided for holding the cover portion 24 during such access. Alternatively, however, the hinged connection between the cover portion 24 and the body portion 22 may be eliminated, thus making the former completely detachable from the latter. In this event, however, the cover portion 24 would be supported by a crane or other suitable means (not shown) during its detachment from the body portion 22.

' As shown in FIG. 2, the illustrated centrifugal compressor comprises four stage centrifugal compressors 40, 42, 44, 46, which are radially disposed within the body portion 22 of the housing 10. The stage centrifugal compressors 40, 42, 44, 46, are each formed to include a casing 48 which contains an impeller 50. The impellers 50 are each fixedly carried by a rotatable impeller shaft 52 which is rotatably journalled in the horizontal end of the body portion 22 opposite to the open horizontal end thereof. The impeller shafts 52 eachcarry a driven gear 54 which meshes with, and is driven by, a driving or bull gear 56 carried bv a driving shaft 58 rotatable by the driving motor 16. Thus, the stage centrifu al com ressors 40, 42, 44, 46, may be driven at individual operating speeds by provid ng diflerent driven gears 54 upon the impeller shafts 52.

The casing 48 of each of t e stage centrifugal compresso s 0, 42. 44, 46. is prov ded with an inte ral in et conduit 60 and an integral outlet conduit 62. The inlet conduit 60 and the outlet conduit 62 of each of the stage centrifu al compressors 40. 42, 44, 46, extend towards the open horizontal end of the body portion 22 and terminate adjacent the juncture of the body portion 22 and the cover portion 24. This construction, as will become apparent from the following description, permits the stage centrifugal com ressors 40, 42, 44, 46, to be automatically. serially connected and disconnected by movement of the cover portion 24 to open and close the open horizontal end of the body portion 22.

An inlet pipe 64 is integrally formed with the body portion 22 for admitting fluid to be compressed by the stage centrifugal compressors 40, 42, 44, 46, into the housing 10. The inlet pipe 64 is adapted for connection to a source of the fluid to be compressed (not shown) and directs the fluid into a housing duct 66 whichis formed adjacent the upper vertical limits of the body portion 22 and sealed from the remainder of the body portion 22 by a closure plate 68. The housing duct 66 is provided with a port 70 which is aligned-with a port 72 communicating with a second housing duct 74 formed in the cover portion 24. The second housing duct 74 communicates through a port 76 with a fluid chamber 78 which is formed within the cover portion 24; The fluid chamber 78, as will be seen from FIG. 4, is defined by the outer walls of the cover portion 24, a closure wall 80 extending transversely across the cover portion 24 intermediate the ends thereof,

a horizontal baffle plate 82 carried by the cover portion 24, and a vertical baffle plate 84 carried by the cover portion 24.

A fluid conduit 86 is carried by the closure wall 80 upon the opposing side thereof from the fluid chamber 78 and communicates with the fluid chamber 78 through a "port 88 formed in the closure wall 80. The fluid conduit 86 abuts the inlet conduit 60 of the first stage centrifugal compressor 40 in end-to-end alignment therewith. The outlet conduit 62 of the first stage centrifugal compressor 40 is in end-to-end alignment and abutment with a discharge transition conduit 89 which is carried by the closure wall 80. The discharge transition conduit 89 communicates through an intercooler 90 carried by the closure wall with a second fluid chamber 92 which is defined by the outer walls of the cover portion 24, the clo-' sure wall 80, the horizontal baflie plate 82, and a vertical baifle plate 94. The second fluid chamber 92 communicates through a port 96 in the closure wall 80 with a fluid conduit 98 which is carried by the closure wall 80. The fluid conduit 98 extends from the closure wall 80 in endto-end alignment and abutment with the inlet conduit 60 of the second stage centrifugal compressor 42.

The outlet conduit 62 of the second stage centrifugal compressor 42 is in end-to-end aligment and abutment with a discharge transition conduit 100 which is carried by the closure Wall 80. The discharge transition conduit 100 communicates through an intercooler 102 carried by the closure wall 80 with a third fluid chamber 104 which is defined by the outer walls of the cover portion 24, the closure wall 80, the vertical baffle plate 94, and a horizontal baflle plate 108. The third fluid chamber 104 communicates through a port in the closure wall 80 with a fluid conduit 112 which is carried by the closure wall 80. The fluid conduit 112 extends from the closure wall 80 in end-to-end alignment and abutment with the inlet conduit 60 of the third stage centrifugal compressor 44.

The outlet conduit 62 of the third stage centrifugal compressor 44 is in end-to-end alignment and abutment with a discharge transition conduit 114 which is carried by the closure wall 80. The discharge transition conduit 114 communicatesthrough an intercooler 116 with a fourth, fluid chamber 118 which is defined by the outer walls of the cover portion 24, the closure wall 80, the horizontal baffle plate 103, and a vertical baflie plate 120. The fourth fluid chamber 118 communicates through a port 122 in the closure wall 80 with a fluid conduit 124 which is carried by the closure wall 80. The fluid conduit 124 extends from the closure wall 80 in end-to-end alignment and abutment with the inlet conduit 60 of the fourth stage centrifugal compressor 46.

. The fourth stage centrifugal compressor 46 forms the final stage of the centrifugal compressor and is disposed with its outlet conduit 62 in end-to-end alignment and abutment with a discharge transition conduit 126 which is carried by the closure wall 80. The discharge transition conduit 126 communicates through an aftercooler 128 with a fifth fluid chamber 130 formed in the cover portion 24. The fifth fluid chamber 130 is defined by the outer walls of the cover portion 24, the closure wall 80, a horizontal baffle plate 132, and the vertical bafile plates 84 and 120.

A discharge port 134 formed in a wall of the coverportion 24 communicates the fifth fluid chamber 130 with a dischargeduct 136 disposed adjacent the upper limits of the cover portion 24. The discharge duct 136.

centrifugal compressors 40, 4'2, 44, '46 are each in end to-end alignment and abutment with their respective connected one of the fluid conduits 86, 98, 112, 124 and the discharge transition conduits 89, 100, 114, 126. Due to this construction, movement of the cover portion 24 to open the open horizontal end of the body portion 22 automatically and simultaneously disconnects each of the inlet conduits 60 and the outlet conduits 62 from their respective connected fluid conduits 86, 98, 112, 124 or discharge transition conduits 89, 100, 114, 126. bimilarly movement of the cover portion 24 to close the open horizontal end of the body portion 22 automatically and simultaneously re-establishes these connections. Furthermore, as the housing ducts 66, 74 communicating the stage centrifugal compressors 40, 42, 44, 46 with the inlet pipe 64 and the discharge ducts 136, 142 communicating such with the discharge pipe 144 are moved into and out of communication by this movement of the cover portion 22, it will be seen that movement of the cover portion 22 also simultaneously connects and disconnects the inlet pipe 64 and the discharge pipe 144 with the stage centrifugal compressors 40, 42, 44, 46. The intercoolers 90, 102, 116, and the aftercooler 128 are all of similar construction and each comprises a plurality of cooling pipes 146 adapted to convey coolant fluid into the path of the fluid being compressed by the centrifugal compressor. Each of said coolers includes a coolant inlet conduit 148 which extends to a coolant chamber 154) formed axially in the cover portion 24. The coolant chamber 150 communicates through a fluid passage 152 formed by an annular plate 154 located in circumferentially spaced relationship to the retaining bolt 28 with a coolant chamber 156 formed within the cylindrical locking member 32. The coolant chamber 156 is connected to a coolant inlet pipe 158 which is, in turn, connected to a source (not shown) of a suitable coolant fluid such as water to introduce coolant fluid into the housing 10. The coolant fluid discharged by each of the intercoolers 90, 102, 116 and the aftercooler 128 is directed through the casing 48 of its respective connected one of the stage centrifugal compressors 40, 42, 44, 46 and subsequently discharged into the body portion 22. As the fluid conduits which convey the discharged coolant fluid during its beforedescribed passage are of substantially similar construction for all of the intercoolers 90, 102, 116 and the aftercooler 128, only those which convey the coolant fluid discharged by the intercooler 90 will be specifically described. It will be understood, however, that this description and all of the disclosure therein contained are equal- 1y applicable to the intercoolers 102, 116 and the aftercooler 128, except that such coolers discharge coolant fluid through the stage centrifugal compressors 42, 44, 46, respectively. Similarly all of the following description pertaining to the first stage centrifugal compressor 40, is equally applicable to the stage centrifugal compressors 42, 44, 46.

As illustrated in FIG. 5, the intercooler 9t) discharges coolant fluid to a coolant outlet conduit 160 which conveys the discharged coolant fluid to an aligned coolant outlet conduit 161 communicating with a fluid chamber 162 formed within the volute casing 48 of the first stage centrifugal compressor 40. The coolant outlet conduit 160 is formed in a wall'of the fluid conduit 86; the coolant outlet conduit 161 is formed in a wall of the inlet conduit 60 of the first stage centrifugal compressor 40. Thus, the coolant fluid connection between the coolant outlet conduits 160, 161 is made and broken by movement of the cover portion 24 relative to the body portion 22. i

A coolant outlet pipe 164 which is connected to the fluid chamber 162 directs the coolant fluid against the wall of the body portion 22 behind the first stage centrifugal compressor 40. The first stage centrifugal compressor 40 is spaced from such wall of the body portion 22 to permit the coolant fluid to pass between such wall and its volute casing 48 to provide additional cooling of the first stage centrifugal compressor 40. The'coolantfluid, after providing this cooling of the first stage centrifugal compressor 40, passes into the body portion 22 and floods such to provide an additional cooling of the stage centrifugal compressors 40, 42, 44, 46. A drain pipe 166 is disposed at the lower limits of the body portion 22 for draining'this coolant fluid from the body portion 22.

From the foregoing, it will be seen that the centrifugal compressor illustrated in FIGS. 1 through 5 is constructed and arranged to provide an exceptionally high degree of cooling of the fluid which it compresses and the portions of the compressor performing the compressing action. It will also be seen that the construction and arrangement of this compressor provides a relatively compact compressor which is readily accessible and wherein the coolant fluid conduit connections and the compressed fluid conduit connections are simultaneously connected and disconnected automatically by the movement of the cover portion 24 relative to the body portion 22.

In the operation of the centrifugal compressor illustrated in FIGS. 1 through 5, the fluid to be compressed is introduced into the housing 10 through the inlet pipe 64 and conveyed, successively, by the housing ducts 66 and 74, the fluid chamber 78, and the fluid conduit 86 to the inlet conduit 60 of the first stage centrifugal compressor 40. After its compression by the first stage centrifugal compressor 40, the fluid passes through the outlet conduit 62 thereof into the discharge transition conduit 88. The discharge transition conduit 88 directs this fluid through the intercooler 90 into the second fluid chamber 92 from whence it is directed by the fluid conduit 98 to the inlet conduit 60 of the second stage centrifugal compressor 42.

The second stage centrifugal compressor 42 compresses the fluid and discharges .the recompressed fluid through its outlet conduit 62 into the discharge transition conduit 100. The'discharge transition conduit 100 directs the recompressed fluid through the intercooler 102 into the fluid chamber 104 from whence the fluid passes through the fluid conduit 112 into the inet conduit 60 of the third stage centrifugal compressor 44.

The third stage centrifugal compressor 44, after again compressing the fluid, discharges it through its outlet conduit 62 and the discharge transition conduit 114 to the fourth fluid chamber 118. The fluid is cooled by the intercooler 116 during its passage from the third stage centrifugal compressor 44 to the fourth fluid chamber 118.

The fourth fluid chamber 118 conveys the fluid to the inlet conduit 60 of the fourth stage centrifugal compressor 46 which, after again compressing the fluid, discharges it through its outlet conduit 62 to the discharge transition conduit 126. The discharge transition conduit 126 conveys the fluid through the aftercooler 128 to the fifth fluid chamber 130 from whence it is directed by the discharge conduit 136 and the discharge pipe 144 from the compressor.

The intercoolers 90, 102, and'116 and the aftercooler 128 receive their collant fluid through the coolant inlet pipe 158, the coolant chamber 156, the fluid passage 152, the coolant chamber 150, and the coolant inet conduits 148. The intercoolers 90, 102, and 116 and the aftercooler 128 discharge their coolant fluid through an outlet conduit to the fluid chambers 162 formed within the volute casings 48 of the stage centrifugal compressors 40, 42, 44, 46. After passing through the casings 48 of the stage centrifugal compressors 40, 42, 44, 46, the coolant fluid passes through the coolant outlet pipes 164 between each of such stage centrifugal compressors and the adjacent wall of the body portion 22 and is discharged into the body portion 22. The cooant fluid is drained from the body portion 22 by the drain pipe 166.

Thus, it will be seen that the coolant fluid cools the fluid being comressed' and, then, cools the stage centrifugal compressors 40, 42, 44, 46 compressing the fluid. In this manner, ahigh degree of cooling efliciency is obtained from the coolant fluid.

In order to obtain access to the compressor, the coolant fluid within the body portion 22 is permitted to drain through the drain pipe 166. Then, the bolts 26 and the retaining bolt 28 are removed to permit detachment of the cover portion 24 from the body portion 22 or, if the cover portion 24 be hinged to the body portion 22, pivotal movement of the former relative to the latter.

This detachment or movement of the cover portion 24 opens the horizontal open end of the body portion 22 and automatica'ly and simultaneously disconnects each and every one of the inlet conduits 60 and the outlet conduits 62 of the stage centrifugal compressors 40, 42, 44, 46 from its communicating fluid conduit or discharge transition conduit. This movement of the cover portion 24 also disconnects the housing ducts 66 and 74 and the discharge conduits 136 and 142 to provide a disconnection of the inlet pipe 64 and the outlet pipe 144 from the stage cen-v trifugal compressors 40, 42, 44, 46. Thus, substantially all of the conduits and ducts through which the fluid being compressed must pass are automatically disconnected by the movement of the cover portion 24, thereby facilitating accessibility to the conduits and ducts as wel as to the stage centrifugal compressors 40, 42, 44, and 46.

In addition, the detachment or movement of the cover portion 24, as will be seen from the drawings, automatically and simultaneously disconnects the coolant inlet and outlet passages communicating with the intercoolers 90, 102, and 116 and the aftercooler 128. Thus, the mere movement of the cover portion 24 relative to the body portion 22 automatically and simultaneously disconnects. both compressed fluid and cooltant conduits.- Conversely, the closing of the open horizontal end of the body portion 22 by the cover portion 24 automatically and simultaneously reconnects all of the foredescribed compressed fluid and coolant conduits.

FIG. 6, wherein all elements and components similar to. parts previously described are identified by the. refer-: ence numeral for their previously described part followed by the suflix a, illustrates an alternative embodiment of the invention. In the embodiment: of the invention. ill-us.- t-rated in FIG. 6, a plurality of radially extending ribs 168 divide the body portion 22a into a plurality of compressor chambers 170, each containing one of the stage centrifugal compressors 40a, 42a, 44a, and 46a. The ribs 168 abut the outer walls of the bodyportion 22a to. insure that each of the compressor chambers 1'10 is fluid: tight and prevent any fluid escaping between the inlet conduits 60a and the outlet conduits 62a and their respective, aligned and abuts ting one of the discharge transition conduits and the fluid:

conduits from intermingling. This embodimentof the in.-.

vention prevents the body portion 22 from being flooded with coolant fluid as is possible in the beforedescribedu embodiment of. the invention. It does. permit, however, the cooling of the compressor volutecasin-gs 48a and: the pass: ing of coolant fluid between the stage centrifugal com-. pressors 40a, 42a, 44a, and 46a, and the outer wall of the body portion 22a-therebehind.

The operation of this embodiment ofithe: invention is. believed to be apparent from the foregoing description.

From the foregoing, it will be-seen that I have provided new and improved means for accomplishing all of the objects and advantages of my-invention.

Although several; embodiments of" my invention have been illustrated and described: in detail, it will be understood that the invention is not limited merely tothese em bodiments but contemplates other embodiments and variations which utiize the concepts and teachings of myinvention.

Having thus described myinvention, I claim:

1. A multi-stage, intercooled, rotary compressor comprising:

a housing having a body portion and a cover-portion detachably connected to said body portion;

inlet means in said housing for admitting fluid to be 'ompressed into said housing;

outlet means in said housing for discharging compressed fluid from said housing;

a plurality of stage rotary compressors disposed within said body portion of said housing and each having an inlet conduit and an outlet conduit;

driving means operatively connected to said stage compressors for driving said stage compressors;

a plurality of cooler means disposed Within said cover portion of said houisng;

coolant conduit means operatively connected to said cooler means for conveying coolant fluid thereto and discharging coolant fluid therefrom;

inlet conduit means communicating said inlet means with the inlet conduit of a first of said stage compressors for conveying fluid from said inlet means to said inlet conduit of said first of said stage compressors;

outlet conduit means communicating said outlet means with the outlet conduit of a second of said stage compressors for conveying fluid discharged through said outlet conduit of said second of said stage com pressors to said outlet means;

a plurality of intermediate conduit means disposed within said cover portion of said housing;

each of said intermediate conduit means extending adjacent one of said cooler means such that fluid passing through said intermediate conduit means is cooled by one of said cooler means; and

each of said intermediate conduit means having its. op-

posing ends communicating with the inlet conduit of one of said stage compressors and the outlet conduitof another of said stage compressors such that fluid discharged through the outlet conduit of said first: of said stage. compressors passes serially through the others of said stage, compressors, before entering the inlet conduit of said second ofsaid stage compressors.

2. A multi-stage, intercooled, rotary compressor ac cording to claim 1, wherein said cooler means andsaid. intermediate conduit means are carried by said cover por-. tion of said housing, and said coolant conduit means includes a first section disposed within said body portion,- of said housing and a second section carried by said cover portion of said housing and communicating with said. first section.

3. A multi-stage, intercooled, rotary compressor ac,- cording to claim 2, wherein the opposing ends of said intermediate conduit means, are in alignment and abutment with said inletand outlet conduits of said. stage, compressors.

4. A multi-stage, intercooled, rotary comp t sor ae cording to claim 3, wherein said inlet and outlet conduits; of said stage compressors extend from said, stage cornpressors towards the opposing ends of said intermediate conduit means and said cover portion is carried by said; body. portion at one of the horizontally extending ends thereot}.

5 .v A multi-stage, intercooled, compressor accordingto; claim 2, wherein said coolant conduit means conveys. coolant fluid discharged by said cooler means adjacent. said stage compressors for cooling said stagecompressors 6 A multi-stage, intercooled, rotary compressor ac; cording to. claim 2, wherein said stage compressors each, include a casing having a cooling chamber therein, and: said coolant conduit means discharges coolant fluid into. said cooling chambers for cooling saidstage compressors.

7. A multi-stage, intercooled, rotary compressor ac cording to claim 2, wherein said coolant conduit means dischargesv coolant fluid into said bodyportion of said housing for cooling said stage compressors, and drain means are provided for discharging coolant fluid" from said body portion-of said housing.

8. A multi-stage, intercooled, rotary compressor according to claim 2, wherein said outlet conduit means includes a sectionwhich is carried by said cover-portionof said housing and which communicates with the outlet conduit of said second of said stage compressors, and said section of said outlet conduit means extends adjacent one of said cooler means such that the fluid carried thereby is cooled by one of said cooler means.

9. A multi-stage, intercooled, rotary compressor according to claim 8, wherein said inlet means includes a section which is carried by said cover portion of said housing and which communicates with the inlet conduit of said first of said stage compressors.

10. A multi-stage, intercooled, rotary compressor according to claim 9, wherein a plurality or rib members extend transversely in said body portion of said housing to divide said body portion of said housing into a plurality of chambers, each of which chambers contains one of said stage compressors.

11. A multi-stage, intercooled, rotary compressor according to claim 9, wherein the inlet conduits and the outlet conduits of said stage compressors extend towards said cover portion of said housing, and said inlet conduit means, said outlet conduit means, and said intermediate conduit means are aligned with and abut their respective communicating ones of said inlet and outlet conduits.

12. A multi-sta-ge, intercooled, rotary compressor according to claim 11, wherein means pivotally connect said cover portion of said housing to said body portion thereof.

13. A multi-stage, intercooled, rotary compressor according to claim 11, wherein hinge means pivotally connect said cover portion of said housing to a horizontally extending end of said body portion of said housing such that said cover portion is carried by said body portion of said housing.

14. A multi-stage, intercooled, rotary compressor comprising:

a housing;

inlet means in said housing for admitting fluid to be compressed into said housing;

outlet means in said housing for discharging compressed fluid from said housing;

a plurality of stage rotary compressors disposed Within a portion of said housing and each having an inlet conduit and an outlet conduit;

driving means operatively connected to said stage compressors for driving said stage compressors;

a plurality of cooler means disposed within said housfirst coolant conduit means operatively connected to said cooler means for supplying coolant fluid thereto; second coolant conduit means for supplying coolant fluid to said portion of said housing containing said stage compressors whereby said housing portion is floodable to submerge said stage compressors in coolant fluid;

drain means in said housing for draining coolant fluid from said housing portion; inlet conduit means connecting the inlet conduit of one of said stage compressors to said inlet means for conveying fluid from said inlet means to said inlet conduit of said one of said stage compressors;

outlet conduit means connecting the outlet conduit of a second of said stage compressors to said outlet means for conveying the discharge of said second of said stage compressors to said outlet means; and

intermediate conduit means extended adjacent said cooler means and having their opposing ends aligned with the inlet conduit of one of said stage compressors .and the outlet conduit of another of said stage compressors such that fluid discharged by the outlet conduit of said first of said stage compressors passes successively through the others of said stage compressors before entering the inlet conduit of said second of said stage compressors.

15. A multi-stage, intercooled, rotary compressor according to claim 14, wherein said second coolant conduit means is connected to said cooler means to receive coolant fluid from said cooler means.

16. A multi-stage, intercooled, rotary compressor according to claim 15, wherein said stage compressors each include a casing having a chamber therein for receiving coolant fluid, and said second coolant conduit means discharge coolant fluid from said cooler means into said chambers.

17. A multi-stage, intercooled, rotary compressor according to claim 16, wherein conduit means communicate with the chambers in the casings of said stage compressors for discharging coolant fluid from said chambers into said housing portion.

18. A multi-stage, intercooled, rotary compressor according to claim 17, wherein the conduit means defined therein directs coolant fluid peripherally on said stage compressors while discharging said coolant fluid into said housing portion.

References Cited UNITED STATES PATENTS 1,265,650 5/1918 Graemiger 230-209 2,945,620 7/ 1960 Caddell 23020-9 3,001,692 9/1961 Schierl 230-209 3,211,362 10/1965 Laskey et al 230-209 HENRY F. RA'DUAZO, Primary Examiner. 

1. A MULTI-STAGE, INTERCOOLED, ROTARY COMPRESSOR COMPRISING: A HOUSING HAVING A BODY PORTIOIN AND A COVER PORTION DETACHABLY CONNECTED TO SAID BODY PORTION; INLET MEANS IN SAID HOUSING FOR ADMITTING FLUID TO BE COMPRESSED INTO SAID HOUSING; OUTLET MEANS IN SAID HOUSING FOR DISCHARGING COMPRESSED FLUID FROM SAID HOUSING; A PLURALITY OF STAGE ROTARY COMPRESSORS DISPOSED WITHIN SAID BODY PORTION OF SAID HOUSING AND EACH HAVING AN INLET CONDUIT AND AN OUTLET CONDUIT; DRIVING MEANS OPERATIVELY CONNECTED TO SAID STAGE COMPRESSORS FOR DRIVING SAID STAGE COMPRESSORS; A PLURALITY OF COOLER MEANS DISPOSED WITHIN SAID COVER PORTION OF SAID HOUSING; COOLANT CONDUIT MEANS OPERATIVELY CONNECTED TO SAID COOLER MEANS FOR CONVEYING COOLANT FLUID THERETO AND DISCHARGING COOLANT FLUID THEREFROM; INLET CONDUIT MEANS COMMUNICATING SAID INLET MEANS WITH THE INLET CONDUIT OF A FIRST OF SAID STAGE COMPRESSORS FOR CONVEYING FLUID FROM SAID INLET MEANS TO SAID INLET CONDUIT OF SAID FIRST OF SAID STAGE COMPRESSORS; OUTLET CONDUIT MEANS COMMUNICATING SAID OUTLET MEANS WITH THE OUTLET CONDUIT OF A SECOND OF SAID STAGE COMPRESSORS FOR CONVEYING FLUID DISCHARGED THROUGH SAID OUTLET CONDUIT OF SAID SECOND OF SAID STAGE COMPRESSORS TO SAID OUTLET MEANS; A PLURALITY OF INTERMEDIATE CONDUIT MEANS DISPOSED WITHIN SAID COVER PORTION OF SAID HOUSING; EACH OF SAID INTERMEDIATE CONDUIT MEANS EXTENDING ADJACENT ONE OF SAID COOLER MEANS SUCH THAT FLUID PASSING THROUGH SAID INTERMEDIATE CONDUIT MEANS IS COOLED BY ONE OF SAID COOLER MEANS; AND EACH OF SAID INTERMEDIATE CONDUIT MEANS HAVING ITS OPPOSING ENDS COMMUNICATING WITH THE INLET CONDUIT OF ONE OF SAID STAGE COMPRESSORS AND THE OUTLET CONDUIT OF ANOTHER OF SAID STAGE COMPRESSORS SUCH THAT FLUID DISCHARGED THROUGH THE OUTLET CONDUIT OF SAID FIRST OF SAID STAGE COMPRESSORS PASSES SERIALLY THROUGH THE OTHERS OF SAID STAGE COMPRESSORS BEFORE ENTERING THE INLET CONDUIT OF SAID SECOND OF SAID STAGE COMPRESSORS. 